Australia Model Code of Practice: Managing the Risks of Plant in the Workplace 4.1b: 4.1 Design, maintain and refit guards so they work and cannot easily be defeated

Guarding must be of solid construction and securely mounted to resist impact or shock; make by-passing or disabling, accidental or deliberate, as difficult as reasonably practicable; not itself create a risk such as obstructing visibility, weakening the plant, causing discomfort or creating pinch points or sharp edges; be properly maintained; control so far as reasonably practicable risks from broken or ejected parts and work pieces; and be removable when the plant is not in normal operation for maintenance and cleaning, with the plant unable to restart unless the guard is replaced where reasonably practicable. Guards removed for maintenance or cleaning must be replaced before normal operation, with the energy source eliminated by disconnecting power or locking out motive power while removed. Consider the environment when choosing a guard (high frequency welders, heat, splashes, corrosion) and consider painting guards a consistent high visibility colour and the surfaces behind them a contrasting colour so a missing guard is obvious.